Conversion of hydrocarbons



INVENTOR. Ey/f/ Jag/W, O

AMW,

Filed July 31,. 1940 G EGLOFF CONVERSION OF HYDROCARBONS March 7, 1944 Patented Mar. 7, 1944 CONVERSION E Gustav Egloil,v Chicago, lll.,

HYDBOCABBONS assigner to'Univerlnl 0 Producti Comm, Chicago, nl... gol-p0- ration o2 Delaware application my si, im, semi No. msu

4 claims. (cl. 19a-sz) This invention relates to a process for convert-` ing hydrocarbon distillate into high yields of antiknock gasoline by subjecting them to theaction of catalytic agents. More particularly it relates to a combination process for reforming naphthas and cracking higher boiling distillate fractions o! petroleum to produce motor fuel.'

Although the charging stocks contemplated in the present invention 'are normally from petroleum sources, it is Within the scope of the invention that similar stocks from other sources should be treated.

In one specific embodiment the present invention comprises a process for converting hydrocarbon oil into high antiknock gasoline which comprises converting a naphtha'fraction of said hydrocarbon oil in a. primary step with or without the addition of 'a catalytic agent, converting higher boiling hydrocarbon oil into gasoline in the presence of a cracking catalyst powder in a secondary cracking step, non-catalyticallyconvertlng light reflux and process gas produced as hereinafter described in a tertiary step, combining the reaction products in a. reaction zone, fractionating said reaction products. recovering gasoline. supplying light reflux and gas to the ter'- tiary cracking step as described, and returning a portion of higher boiling reflux for further conversion in said primary step.

The invention is further understood by reference to the accompanying drawing which is diagrammatic and should not be interpreted as limiting the process unduly.

A naphtha charging stock is introduced through line I. valve 2, pump 3 and valve 4 to coil 5 which is disposed in reforming heater 5. The temperature in the coil is within the range of 900l200 F. and at a pressure of substantially atmospheric to 1000 pounds per square inch or higher. The conditions used depend to a certain extent upon the charging stock undergoing conversion and as to whether thermal non-catalytic or catalytic reforming is being used. If a catalyst is to be employed, somewhat lower temperature conditions can be maintainedin the reforming coil if desired. When using a catalyst, it is introduced from catalyst charger 'l through line 8, valve 9, pump i4 and valve H. passing through line to coil 5. The character and composition of the catalyst may vary considerably. Suitable catalysts will be described in more detail in a later section. The reaction products pass through line I2 and valve i3 to line I4 and thence through valve I5 to reaction chamber I6. Higher boiling hydrocarbon oil charging stock such as gas oil,

kerosene distillate, wax

dumme and the like is introduced through line I1. valve I8. pump I9 and valve 2l to coil 2| which. is disposed in heater 22. The oil is mixed with catalyst from charger,

23, passing through valve 24. pump 25 and valve 2i to Yline l1. The catalyst may be in the form of a slurry in a portion other suitable medium. Considerable cracking occurs in coil 2| which is maintained at tempera,- r

tures within the range of approximately 500.-1200 F. and pressures of 1000 pounds per square inch. The reaction products pass through line 21 and valve 28, joining with the reaction products from coil 6 in line I4.

The temperature conditions in reactor I6 are.

'within the range of approximately 500-1000 F., although somewhat higher temperatures may also be-employed. The reaction produc'ts containing catalyst in suspension pass valve 30 to fractionator 3|. Gas and gasoline pass through line 32, valve 33, condenser 34,` valve 35 to receiver 3B. The gasoline .is recovered through line 31 containing valve 38 andmay be withdrawn to storage or such additional treat-y to produce lfinished i ment as may be necessary product. A portion of the gas may be passed through line 39 and valve ,40 to a suitable gas recovery system not shown. A portion of the gas l is passed through line, valve 42, pump 43 and valve 44 to line 45 with a light reflux boiling substantially above the gasoline range, entering from line 41 through valve 48 and pump 49. The mixture is passed to coil 50 which is disposed in heater 5|. The vmixture passes through line 52 and valve 53 to line I4 and is thus returned to reactor I6. The temperature and pressure conditions maintained in coil 50 are adequate to obtain substantial conversion of the hydrocarbon oil being within the range of approximately o-1200n F. and a pressure of 10o-1000 pounds per square inch or higher. A heavy reux is removed through line 54, valve .55, pump 56 and valve 51, passing to line I and thus being recycled for further conversion. A residual fraction is withdrawn from fractionator 3| through line 58 and valve 59. This fraction contains spent catalyst in suspension and the catalyst may be recovered therefrom and reactivated have been activated by treatment with acids.

of a chargingstock or ,v

substantially atmospheric to through line 29 and and valve 46. It is mingled Another type of catalyst. which is preferred in the cracking step, is the so-called silica-alumina, silica-zirconia, silica-alumina-zirconia, etc., type of catalyst which may be used alone or may have promoting oxides of metals such as chromium, molybdenum, tungsten, vanadium, uranium, thorium, titanium.' etc., deposited thereon. These composites are made by the separate or simultioned are not necessarily Yequivalent and identical results may not be obtained by the substitu.

tion of one for another. 'Moreoveig certain of the catalysts are more active for the cracking step and certain others for the reforming step, and it is within the 'scope of the invention that different catalysts should be used in each of these steps. v

The following example is given to illustrate the usefulness and practicability of theprocess, but should not be construed'as limiting it'to the exact conditions or catalysts given therein. Y

A Mid-Continent gas oil and' naphtha kare cracked according to the present process, using a sodium ion-free silica-alumina catalyst having deposited thereon a minoramountof chromium oxide; the same type of catalyst being used in both the cracking and the reforming steps. The reforming step maybe carried out at ll F. and the cracking step at 1000 F., both being at approximately 2500 pounds per square inch pressure. The thermal cracking step in which gas and light reflux is cracked is carried out at 1050 F. and 500 pounds per square inch pressure. The pressure maintained in the reaction chamber is approximately pounds per square inch. A total yield of approximately 70% of 400 F. endpoint gasoline having an 'octane number of 78 may be obtained in this way. Additional quantities of gasoline are obtainable by polymerizing a portion of the gases withdrawn from the process.

I claim as my invention:

l. A process for the conversion of hydrocarbon oil which comprises subjecting a naphtha to catalytic reforming in the presence of a powdered dehydrogenating catalyst suspended therein, subjecting a gas oil to catalytic cracking in the presence of a powdered cracking catalyst suspended therein, combining conversion productsr containing the catalysts from both steps, subjecting the mixture to continued conversion in a reaction chamber, separating the resulting conversion products into liquid residue containing the catalysts and cracked vapors, fractionating said cracked vapors to form light and heavy reux condensates, recovering the fractionated vapors, returning the heavy reflux condensate to the reforming step, thermally cracking said light reflux condensate, and supplying cracked products from the thermal cracking step to said reaction chamber.

2. The process of claim l further characterized in that the fractionated vapors are subjected to cooling and condensation, the 'resulting distillate and undissolved and uncondensed gases collected and separated, and said undissolved and uncondnsed gases supplied to the thermal cracking s p.

3. A conversion process which comprises subjecting a relatively light hydrocarbon oil containing naphtha fractions to catalytic reforming in the presence of a dehydrogenating catalyst suspended therein, independently subjecting a heavier hydrocarbon oil to catalytic cracking in the presence of a cracking catalyst suspended therein, combining conversion products and catalysts from the conversion steps, subjecting the mixture of hydrocarbon conversion products to continued conversion in the presence of the mixed catalysts, fractionating resultant vaporous conversion products to separate -a gasoline boiling range fraction and to condense as reflux condensate fractions higher boiling than said gasoline fraction, and supplying at least a portion of said reflux condensate to the catalytic reforming step.

4. The process of claim 3 further characterized in that the fractions higher boiling than gasoline are condensed as light and heavy reflux condensate fractions and the heavy reflux condensate fraction is supplied to the catalytic reforming step.

GUSTAV EGLOFF. 

